Last month, Twitter quietly rolled out a new feature to give users the choice to receive private messages from any of their followers, but that option has now been removed.

A checkbox to opt in to the feature was previously found under the account settings, but it is no longer there. This means Twitter users are back to being unable to send a direct message to someone in their follower list if their chosen recipient isn’t following them back.

In response to this, Twitter seems to be emphasizing that it is constantly releasing experiments — and this feature is just one of them.

I asked Twitter why the “accept DMs from anyone” feature is gone, and all I got was a link to this post: https://t.co/HMfDnHiEn6

Pointing the press to this very post is Twitter’s standard response to questions about features that appear or disappear on the service.

In any case, the fact that Twitter actually zoomed in to focus on direct messages — one of its oldest features — suggests that rumors about the company considering developing a standalone mobile app for its DM service may have had some ground after all.